Schedule IV - Mortgage Loans on Real Estate (Details) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) loan	Dec. 31, 2015 USD ($) loan
Movement in Mortgage Loans on Real Estate [Roll Forward]
Residential whole loans, at carrying value, beginning balance	$ 271,845
Residential whole loans, at fair value, beginning balance	623,300
Residential whole loans, at carrying value, ending balance	590,540	$ 271,845
Residential whole loans, at fair value, ending balance	$ 814,682	623,300
Residential whole loans
Mortgage Loans on Real Estate [Line Items]
Number (loans) \| loan	7,038
Balance Sheet Reported Amount	$ 1,405,222
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 771,424
Residential whole loans \| Carrying value
Mortgage Loans on Real Estate [Line Items]
Number (loans) \| loan	3,226
Balance Sheet Reported Amount	$ 590,540
Principal Amount of Loans Subject to Delinquent Principal or Interest	76,142
Movement in Mortgage Loans on Real Estate [Roll Forward]
Residential whole loans, at carrying value, beginning balance	271,845
Purchases and capitalized advances	363,089
Yield accreted	23,916
Collection of principal	(44,692)
Collection of interest	(21,428)
Provision for loan loss	175
Repurchases	0
Transfer to REO	(2,365)
Residential whole loans, at carrying value, ending balance	$ 590,540	$ 271,845
Residential whole loans \| Fair value
Mortgage Loans on Real Estate [Line Items]
Number (loans) \| loan	3,812	3,143
Balance Sheet Reported Amount	$ 814,682
Principal Amount of Loans Subject to Delinquent Principal or Interest	695,282
Movement in Mortgage Loans on Real Estate [Roll Forward]
Residential whole loans, at fair value, beginning balance	623,276
Purchases and capitalized advances	316,407
Collection of principal	(66,694)
Changes in fair value recorded in gain/(loss) on loans recorded at fair value	31,254
Repurchases	(2,909)
Transfer to REO	(86,652)
Residential whole loans, at fair value, ending balance	$ 814,682	$ 623,276
Original loan balance $0 - $149,999 \| Residential whole loans \| Carrying value
Mortgage Loans on Real Estate [Line Items]
Number (loans) \| loan	1,189
Balance Sheet Reported Amount	$ 82,718
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 16,826
Original loan balance $0 - $149,999 \| Residential whole loans \| Carrying value \| Minimum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	0.00%
Original loan balance $0 - $149,999 \| Residential whole loans \| Carrying value \| Maximum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	13.08%
Original loan balance $0 - $149,999 \| Residential whole loans \| Fair value
Mortgage Loans on Real Estate [Line Items]
Number (loans) \| loan	1,268
Balance Sheet Reported Amount	$ 101,448
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 71,868
Original loan balance $0 - $149,999 \| Residential whole loans \| Fair value \| Minimum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	1.00%
Original loan balance $0 - $149,999 \| Residential whole loans \| Fair value \| Maximum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	14.99%
Original loan balance $150,000 - $299,999 \| Residential whole loans \| Carrying value
Mortgage Loans on Real Estate [Line Items]
Number (loans) \| loan	1,107
Balance Sheet Reported Amount	$ 168,636
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 19,800
Original loan balance $150,000 - $299,999 \| Residential whole loans \| Carrying value \| Minimum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	1.00%
Original loan balance $150,000 - $299,999 \| Residential whole loans \| Carrying value \| Maximum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	11.00%
Original loan balance $150,000 - $299,999 \| Residential whole loans \| Fair value
Mortgage Loans on Real Estate [Line Items]
Number (loans) \| loan	1,324
Balance Sheet Reported Amount	$ 217,555
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 176,177
Original loan balance $150,000 - $299,999 \| Residential whole loans \| Fair value \| Minimum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	1.80%
Original loan balance $150,000 - $299,999 \| Residential whole loans \| Fair value \| Maximum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	12.38%
Original loan balance $300,000 - $449,999 \| Residential whole loans \| Carrying value
Mortgage Loans on Real Estate [Line Items]
Number (loans) \| loan	469
Balance Sheet Reported Amount	$ 126,681
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 15,258
Original loan balance $300,000 - $449,999 \| Residential whole loans \| Carrying value \| Minimum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	1.31%
Original loan balance $300,000 - $449,999 \| Residential whole loans \| Carrying value \| Maximum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	9.75%
Original loan balance $300,000 - $449,999 \| Residential whole loans \| Fair value
Mortgage Loans on Real Estate [Line Items]
Number (loans) \| loan	621
Balance Sheet Reported Amount	$ 176,389
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 155,087
Original loan balance $300,000 - $449,999 \| Residential whole loans \| Fair value \| Minimum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	1.87%
Original loan balance $300,000 - $449,999 \| Residential whole loans \| Fair value \| Maximum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	11.00%
Original loan balance greater than $449,999 \| Residential whole loans \| Carrying value
Mortgage Loans on Real Estate [Line Items]
Number (loans) \| loan	461
Balance Sheet Reported Amount	$ 212,505
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 24,258
Original loan balance greater than $449,999 \| Residential whole loans \| Carrying value \| Minimum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	1.25%
Original loan balance greater than $449,999 \| Residential whole loans \| Carrying value \| Maximum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	8.50%
Original loan balance greater than $449,999 \| Residential whole loans \| Fair value
Mortgage Loans on Real Estate [Line Items]
Number (loans) \| loan	599
Balance Sheet Reported Amount	$ 319,290
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 292,150
Original loan balance greater than $449,999 \| Residential whole loans \| Fair value \| Minimum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	0.00%
Original loan balance greater than $449,999 \| Residential whole loans \| Fair value \| Maximum
Mortgage Loans on Real Estate [Line Items]
Interest Rate	10.88%

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value, Repurchases

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Fair value at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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The amount of principal collected on mortgage loans on real estate during the reporting period.

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The stated interest rate on the mortgage loan receivable or the weighted average interest rate on a group of loans.

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Total amount of new mortgage loans on real estate during the reporting period.

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Indicates the number of mortgages under each classification.

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Amount of principal due on loans that have been delinquent, which may exclude loans having interest delinquent for three months or less, as of the balance sheet date.

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